Alloy



- Patented June 8, 1943 Y UNITED ALLoY William 0. McLott, Grand Rapids,Mich.

No Drawing. Application August 6, 1941,

' Serial No. 405,627

4 Claims.

This invention relates to a new alloy of which the principal ingredientsare iron, chromium, molybdenum and copper with small amounts of titaniumand manganese, carbon and silicon. The alloy may be used in the form ofa weld rod in oxyacetylene and electric welding. In connection withelectric welding, because of the ve y high temperatures produced aspecial and novel flux must be used and my invention is concerned notonly with the metallic alloy but also with the flux required in theelectric welding or deposi- 3 tion of the metal alloy.

In the alloy-which I have produced the chromium and molybdenum usedprovide an exceptionally tough bond, which is three or four timesgreater than the best high test steels to hold the copper in minutecrystalline structure in the alloy. The copper converts to a hexagonalcrystal of an extremely small size which is much harder and tougher thanpractically any known synthetic substance and which crystals do not meltin passing through the electric arc.

The alloy combination when melted and deposited properly onto a preparedsurface is bonded thereto by a small amount of the chromium andmolybdenum of the melted alloy unit ing with the base metal, producing avery strong bond which holds the very hard alloy upon the base in abetter and superior manner to anything which I have previously known.The alloy is not designed to serve as a cutting edge for metal turningbut holds an edge well for-rock cutting, food chopping or other placeswhere a keen edge is not required, for example on axes and various typesof cutting knives such as those cutting ensilage and the like. The alloymay be readily applied to gray cast iron or to any steel base depositingthereon in either a single layer or in successive layers. A good flux toclean oxide from the surface of the base is requisite in order for' thealloy to unite with and form a tough bond.

The alloy which I have produced possesses an aflinity for tungstencarbide adhering thereto with great strength so that it can be removedonly by grinding or oxidizing at high temperatures. This makes itvaluable for the setting of carbide inserts to fishtail bits and corebits in rock drilling such as in drilling oil wells and in miningoperations. It also may be applied to parts which are subsequently to becarbomzed or nitrited. The specific gravity of the alloy issubstantially the same as that of steel so that it does not bury itselfby gravity in molten steel or in the molten surface of a steel .basewhen applied thereto.

I have found that any alloy composed of chromium of approximately 25 to33%, molybdenum 15% to 5%, copper 1 to 3%, manganese 0.5 to 2%, titanium0.3 to 1.5% with carbon 3 t0 3.25% and silicon 0.7 to 1.3%, the balancebein of iron produces an alloy which is very hard and resistant toabrasion; has a high strength and which canvbe deposited either byoxy-acetylene or electric arc melting. The metal thus deposited has ahardness from 610 to 650 Brinnell, the lower degrees ofhardness beingthat when deposited and bonded to a mild or tool steel base and thehigher degrees when deposited on bases of' high alloy or manganesesteels. The tensile strength ranges from 90,000 to 110,000 pounds persquare inch. Its resistance to. abrasion as compared to that of thediamond is as "19 to 100. The melting point is approximately 2400f F.,its specific gravity is substantially 8.3. There is no elongation attemperatures under 1800" F. and scarcely and at the worst but a veryslight elongation at temperatures over 1800 F. deposits of the alloy may.be laid one upon another without removal of a previous or old deposit,this being an advantage in the repair of previous deposits or overlays.

The titanium used accelerates the proper relation of the chromium, ironand carbon with an increase in the production of iron chrome carbide.The manganese to and including 0.5% is used to control sulphur andphosphorus and that used above 0.5% acts to cause the formation of aPenta carbide of chrome iron.

The-alloy in the form of rods may be used without any flux coating inthe oxy-acetylene melting of the rods and their deposition upon a base.

The temperature of the melting flame will not 7 elements comprisesmarble 38 to 42%, graphite 35 to 38%, fluorspar 15 to 18%, titanium, 6to 8%;

and when the smaller percentages are used any balance required to makethe full 100% is oi-a' diatomaceous earth. The liquid elements used aresodium silicate 30% and distilled water The liquid and dry elements aremixed'to ether Succeedin in proportions of 55% of dry elements to 45% ofwet elements.

In applying the flux coating to the rods the amount used is such thatthe dry element weight of the flux approximates 6% of the total weightof the rod while the metallic alloy consists of the remaining 94% of theweight.

The marble, graphite and fiuorspar and a diatomaceous earth provide theoxygen exclusion feature of the flux while the titanium in the fluxinsures against the detrimental effects of nitrogen in the air combiningwith elements of the alloy composition to the detriment of the deposit.

The present alloy may be readily welded on steel of any carbon contentand on cast iron and all types of alloy steels. The phosphorus andsulphur which may be present in very small amounts because unavoidableare counteracted as to their effect by use of manganese, and copper inits minute crystalline: form provides an extremely hard and toughconstituent which is not affected as to its properties when subjected tothe high temperatures present in electric melting and depositing of themetal.

The most essential components of the alley in addition to the iron arethe chromium, molybdenum and copper. The carbon and silicon are inproper balance, the manganese need only be used in the amount to controlthe phosphorus and sulphur, but the alloy is bettered by the smallamounts which may be used in addition to the minimum amount ofapproximately .5%. The alloy has many useful applications as previouslyrecited and also may be used in many other in stances not mentioned,particularly where a resistance to wear is desirable, for example, onthe lips or teeth of steam shovel buckets handling rock. The hardness ofthe alloy approaching substantially that of the sapphire, is such thatthe usual abrasive action of rock does not afiect it. The intimate bondof the chromium, molybdenum and iron with the metal of the base uponwhich the alloy is deposited provides complete assurance againstseparation therefrom.

I claim:

1. A strong, tough and abrasive resistant alloy adapted to be meltablydeposited upon a ferrous base consisting of chromium between 25 and 33%,molybdenum between 1.5 and 5%, copper between 1 and 3%, manganesebetween 0.5 and 2%, titanium between 0.3 and 1.5% with carbon between 3to 3.25% and silicon between 0.7 to 1.3%, the balance being of iron withnegligible quantities of the usual impurities.

2. An alloy of the class and for the purposes described composed ofchromium approximately 25 to 33% molybdenum between 1.5 and 5%, cop perbetween 1 to 3%, titanium between 0.3 to 1.5% with carbon approximating3% and silicon 0.7 to 1.3%, the balance being of iron with the usualnegligible quantities of impurities controlled by the use of manganesein the alloy of approximately 0.5%.

3. An alloy having the properties and for the purposes describedcomposed of chromium between 25 to 33%, molybdenum, 1.5 to 5%, copper 1to 3%, with carbon between 3 and 3.25%,

and silicon between 0.7 and 1.3%, the remainder being iron.

4. An alloy in which the main ingredient is iron and which containsapproximately 30% chromium, 3% molybdenum, 2% copper, 1% titanium, 1.5%manganese, 3% carbon and 1% silicon, said iron having the usualnegligible phosphorus and sulphur impurities.

WILLIAM C. McLO'I'l.

